ABSTRACT
A great diversity of antigens from Mycobacterium leprae have been described. One practical approach should be to utilize them as markers to indicate when a household contact is at risk of becoming infected and then moving to an active form of leprosy. For this purpose, sonic extracts of M. leprae were fractionated in 10% SDS-PAGE under reducing conditions. The fractionated proteins were then transferred to nitrocellulose sheets and incubated with sera from lepromatous leprosy cases, their contacts, and normal subjects in order to reveal the frequency of antigen recognition of each set of sera. The results showed that sera from lepromatous leprosy patients frequently recognized two proteins, one of approximately 28 kDa and the other of approximately 65 kDa, when compared with the sera from normal subjects. The contacts frequently recognized an approximately 16-kDa antigenic band, while sera from normal subjects recognized one protein of approximately 18 kDa. According to the results, the four recognized proteins from M. leprae can be considered markers of the above conditions (approximately 65 kDa, approximately 28 kDa for lepromatous leprosy, approximately 16 kDa for contacts, and approximately 19 kDa for normal subjects). From these, an easy serological test, such as an ELISA, can be developed to predict if a contact is moving toward lepromatous leprosy before detection of the actual clinical signs or symptoms.
Subject(s)
Antibodies, Bacterial/immunology , Antigens, Bacterial/immunology , Leprosy, Lepromatous/immunology , Mycobacterium leprae/immunology , Adult , Aged , Antigen-Antibody Reactions , Blotting, Western , Contact Tracing , Electrophoresis, Polyacrylamide Gel , Epitopes/immunology , Female , Humans , Immunoglobulin G/immunology , Male , Middle Aged , Molecular WeightABSTRACT
The incorporation of (3H) thymidine and the biosynthesis of interleukin-2(IL-2) were investigated in Concanavalin A (ConA) and histoplasmin stimulated lymphocytes from spleen of infected Balb/c mice with the yeast phases of Histoplasma capsulatum. The ability to incorporate (3H) thymidine of Con A stimulated lymphocytes in culture from spleen of Histoplasma capsulatum infected mice, as well as the IL-2 content present in the supernatants of that cultures, were depressed along the first three weeks of the experiments, but starting week five, normal values were restored or even discretly increased. Incorporation of (3H) thymidine in histoplasmin stimulated lymphocytes remained inhibited along the seven weeks the experiment lasted. Results showed that inoculation of H. capsulatum yeast in mice provoked a temporary immunosuppression on cell mediated immunity, that can be explained by means of the inability of T cells to produce enough IL-2 necessary for the proliferation of T cells in culture.
Subject(s)
Histoplasmosis/immunology , Interleukin-2/biosynthesis , Lymphocytes/immunology , Thymidine/metabolism , Animals , Cells, Cultured , Concanavalin A/immunology , Histoplasmin/immunology , Histoplasmosis/metabolism , Immunity, Cellular , Male , Mice , Mice, Inbred BALB CABSTRACT
When Dengue type 2 virus (DEN-2) is put in contact with spleen cells from DBA/2 mice that had been stimulated with Concanavalin A, it was found a decrease in the incorporation of (3H) Thymidine. Furthermore it was observed that the number of Antibody forming cells (Plaque forming cells) against SRBC was decreased, when lymphocytes from DBA/2 mice spleen in culture, had been stimulated with sheep red blood cells (SRBC) in vitro and then infected with DEN-2 virus and the interleukin-1 (IL-1) biosynthesis was quantified in the thymocyte system it was shown that macrophages produced high levels of IL-1 compared with non-infected cells, and that this increased levels could be similar to that produced when macrophages are stimulated with lipopolysaccharide form E. Coli (LPS). The above mentioned results suggest that DEN-2 virus is able of altering some functions of the immune response concerning T and B lymphocytes. Furthermore, the infection of P388D1 cells induce in the first 24 hours an over production of IL-1 that could be the reason why in the natural infection in humans, patients run a fever in the beginning of the viremia caused by DEN-2 virus related with the property of IL-1 reported as endogenous pyrogen.
